Sand-blast machine.



No. 807,036. I PATENTED 111:0. 12, 1905.

- G. W. & w. H. LE-IMAN.

SAND BLAST MACHINE.

APPLICATION FILED JUNE 3, 1905.

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UNITED STATES PATENT QFFIGE.

GEORGE W. LEIMAN AND WILLIAM H. LEIMAN, OF NEW YORK, N. Y.

4 SAND-BLAST MACHINE.

To all whom, it may concern:

Be it known that we, GEORGE W. LEIMAN and WILLIAM H. LEIMAN, citizens ofthe United States, and residents of the borough of Manhattan, in thecity and State of New York, have invented a new and useful Sand-BlastMachine, of which the following is a specification.

This invention relates to a sand-blast machine with the object in viewof providing a continuous blast of great efliciency.

In the accompanying drawings, Figurel is aview of the machine inperspective. Fig. 2 is a vertical section. Fig. 3 is a view in detail ofthe sand-ejecting nozzle, and Fig. 4 is a view in detail of the meansfor preventing clogging at the start. I

The body of the machine is denoted by 1 and is supported upon legs 2,the top being slanted and provided with a transparent window 3 forenabling the observer to watch the eifect of the sand upon the articlewhich is being operated upon. The body is provided with arm-holes 4 and5, to the walls of which flexible sleeves 6 and 7 are secured, as isusual, to protect the forearms. of the operator down to the wrist, andfor the purpose of preventing the waste of sand which may lodge aroundthe wrists of'the operator and which when the operators arms arewithdrawn has heretofore been scattered on the floor we provide aslanting wall 8 along the front of the ma:

chine below the arm-holes, the lower edge of said wall being attached tothe front of the machine, forming a kind of trough or hopper immediatelyunderneath the arm-holes for catching the waste sand, and from thistrough we provide an opening 9, covered by a trapdoor 10, for thepurpose of passing the sand from the hopper into the body of themachine, to be brought again into use.

The bottom of the body of the machine slants rearwardly, as shown at 10,and the sides con.- verge toward the top of a sand-receptacle 11, fromwhich thesand is blown to do its work. In the sand-receptacle 11 thereis located a funnel-shaped inlet 12, with its larger end lowermost andlocated slightly above the bottom of the sand-receptacle, so as to leavea layer of sand at all times between the end of the inlet-funnel 12 andthe bottom of the sandreceptacle. From the top of the said inletfunnel12 a sand-feed pipe 13 extends upwardly and then curves over at itsupper end and downwardly into a mixing-chamber 14. The mixing-chamber 14has a contracted lower Specification of Letters Patent.

Application filed June 3, 1905. Serial No' 263,545-

Patented Dec. 12, 1905.

portion 15, from which the sand-ejecting spout or nozzle 16 projects,and in alinement with saidnozzle 16 within the mixing-chamher we locatean air-jet tube 17, which extends downwardly into thegradually-contracting bottom of the mixing-chamber and terminates ashort distance above the top of the ejectornozzle 16 for the purpose ofpermitting the sand from the sand-feed tube to flow down themixing-chamber into the space around and below the air-jet tube 17. Theair-supply pipe 18 leads from the air-jet tube 17 upwardly and off inany desired direction to a suitable supply of air under pressure. (Notshown.)

The sand-feed pipe leads into the side of the mixing-chamber above thelower end of the air-jet tube 17, so that the discharge of air from theair-jet tube into the sand-ejecting nozzle produces a suction tending todraw the sand from the sand-tube 9 to the extent of removingair-pressure from the sand-feeding tube and leaving the sand free to beforced up without any back air-pressure.

A sand-lifting jet of air under pressure is conducted by means of a pipe19, leading from the air-supply pipe 18 to the bottom of thesand-receptacle, where it opens into the sand-receptacle immediatelybelow the mouth of the sand-inlet funnel 12. This sand-lifting jet-pipe19 is provided with a valve 20 for controlling the amount ofair-pressure which shall be admitted to the bottom of the sand-box tolift the sand through the sandfeed pipe.

To prevent the sand from settling down and forming an obstruction to theflow of the sandlifting air-jet in starting the machine, we provide anagitator consisting of a short plunger 21, which is seated in the bottomof'the tubular extension 22 at the bottom of the sandbox and which iscapable of a limited vertically-reciprocating movement across the end ofthe pipe 19, where it connects with this tubular extension at the bottomof the sandbox. By simply forcing the plunger 21 upwardly and permittingit to drop back to its seat the sand which may have settled in a compactmass at this juncture is readily loosened to permit the sand-raising jetto work effectively.

In operation the amount of air-pressure required to force the sand fromthey sand-box to the sand-ejecting nozzle is reduced to a minimum,because of the suction produced at the discharge end of the sand-feedingpipe,

and the jet of air which drives the sand against the surface to beoperated upon is directed along the axis of the sand-ejecting nozzle, sothat the sand which is distributed around it and which reaches thesand-ejecting nozzle under a considerable velocity due to the freedomwith which it is forced through the sandfeed pipe has its motionaccelerated to a high degree of eiiiciency, causing the work to be donevery rapidly and economizing air under pressure.

What we claim is 1. In a sand-blast machine, a mixing-chamber, asand-ejecting nozzle in communication with the mixing-chamber, anair-jet nozzle located within the chamber with its discharge end inproximity to the inlet end of the said nozzle, a sand-feed pipe openinginto the mixing-chamber at a point above the discharge end of theair-jet tube and means for lifting dry sand through the sand-feed pipe.

2. A sand-blast machine comprising a mixing-chamber, a sand-feed tubeconnected with one side of the chamber, a sand-ejecting nozzle connectedwith the chamber, an air-jet nozzle projecting within the chamber pastthe end of the sand-feed tube and in alinement with the sand-ejectingtube, a sand-receptacle and an air jet tube connected with thesand-receptacle for lifting dry sand from the receptacle through thesand-feed tube.

3. A sand-blast machine comprising a mixing-chamber, a sand-ejectingnozzle connected with the mixing-chamber, an air-jet tube projectinginto the chamber in alinement with the sand-ejecting nozzle, asand-receptacle, a sandfeed tube having a funnel-shaped inlet locatedwithin the sand-receptacle and having its opposite end connected withthe side of the mixing-chamber at a point above the mouth of the air-jettube and an air-tube connecting the air-supply pipe with the interior ofthe sand-receptacle below the mouth of the said feed-pipe wherebysuction is produced upon one end of the sand-feed pipe and pressure uponthe opposite end by the action of the air.

4. In a sand-blast machine, the combination with a sand-receptacle, asand-ejecting nozzle, means for directing an air-jet through thesand-ejecting nozzle and means for directing an air-jet to the interiorof the sand-receptacle, of a sand-feed pipe having its discharge endlocated in proximity to the air-jet directed through the sand-ejectingnozzle and its inlet end Within the sand-receptacle in proximity to theend of the air-jet pipe connected therewith whereby suction is producedat one end of the said feed-pipe and pressure at the opposite end.

5. In a sand-blast machine, the combination with a sand-receptacle, asand-feed pipe and an air-jet located in the sand-receptacle for liftingthe sand from the receptacle into the sand-feed pipe, of a mechanicalagitator located at the juncture of the sand-receptacle and air-jet pipefor loosening the sand in starting the machine.

In testimony that we claim the foregoing as our invention we have signedour names, in presence of two witnesses,this 1st day of June,

GEORGE W. LEIMAN. WVILLIAM H. LEIMAN. Witnesses:

FREDK. HAYNES, C. S. SUNDGREN.

